Unlike on Windows 9x where every DLL above 80000000h is visible to all processes you have to inject your hook DLL into every process that might call NtCreateProcess (direct or indirect). Thus injecting the DLL in only one process does not change the code in other processes scopes thus leaving the handling of the function there just as if nothing was done with it.

To install a global hook as you wish to you need to load your library into all processes. Please note that there are two ways to do this:
1. Use uall's functions for DLL Injection (to do this on-the-fly
2. Use NTs automatic DLL loading feature using the registry (App Init settings)_________________Das Problem ist die Entscheidung!